The present invention relates to gauges for measuring the quantity of fuel oil within a fuel storage tank of the type commonly installed in homes and business establishments. More specifically, the invention provides an improvement by adaptation of a rising stem type fuel oil measuring gauge.
At present, heating fuel oil consumers measure the quantity of fuel oil remaining within their storage tanks either by measuring gauges mounted directly on or close to the storage tank, or in the alternative, by relying on the degree day system of oil companies. Each of these methods has distinct disadvantages for the consumers.
Firstly, reliance on a degree day system may be ineffective since such a system is based on estimations. If usage patterns differ from the norm on which the degree day system is based, the consumer may have unknowingly used more fuel oil than he suspects, thus running the risk of depleting his storage tank before ordering a refill. More importantly, consumers are using additional sources of heat, such as wood stoves or solar energy, which can adversely affect degree-day calculations.
Likewise, reliance on fuel gauges mounted on or near a fuel storage tank may result in similar consequences. Fuel tanks are generally located in remote areas of a home or business, as for example in basements. Thus, the fuel gauge associated with the tank is not readily observable and the owner may not be conscious of the quantity of fuel oil remaining within the tank. As such, the owner may not be aware of the time when a refill of the tank is needed, thereby running the risk of depleting his entire supply.
A type of fuel-indicating gauge in common use, mounted on the top of fuel oil storage tanks in homes and businesses, is known as a rising stem gauge. This gauge includes a level-indicating element, or disc, mounted horizontally at the upper end of a vertically rising stem, or shaft, enclosed within a transparent tube. The vertically rising shaft extends into the tank and is mechanically connected to a buoyant float which rests on the surface of the liquid within the tank. Markings on the tube correspond to specific quantities of fuel oil remaining in the associated tank. The quantity of fuel remaining within the storage tank is determined by observing which marking on the tube is aligned with the level-indicating disc within the tube.
The present invention provides an improvement by adaption to a rising stem fuel gauge by having means for providing a remote alarm signal to indicate when the quantity of fuel within the storage tank has been depleted to the level that imminent replenishment of fuel oil is necessary.